Hello reading your post there is no specific functionality build in to email anyone but the admin email.
Personally myself I have never tried that suggestion and it may work for sending email to yourself and others but you will have an issue trying to send email since that can only be one email address in the TO field and not multiple ones.
More than likely based on your post I would state you might want to investigate the possibility of writing your own email function or thinf about code mods that might do what you want it to do.
Here are a couple things that should help you here. This is a post about our companies policies and use of the mod forums
http://www.photopost.com/forum/showthread.php?t=121154
This is the actual forum you might want to discuss code hack ideas in.
http://www.photopost.com/forum/photopost-pro-mod-discussions/